Machine for shredding paper or the like into strips



F. T. LEE

Nov. 13, 1.956

MACHINE FOR SHREDDING PAPER OR THE LIKE INTO STRIPS 4 Sheets-Sheet 1Filed Jan. 8, 1952 IN VEN TOR.

FILEZMON T.

LEE

ATTORNEYS zmwoz F. T. LEE

Nov. 13, 1956 MACHINE FOR SHREDDING PAPER OR THE LIKE INTO STRIPS 4Sheets-Sheet 2 Filed Jan. 8, 1952 INVENITOR.

F l L. EMON T. E E

ATTORNEYS 13, 1956 F. T. LEE 2,770,30z

MACHINE FOR SHREDDING PAPER OR THE LIKE INTO STRIPS Filed Jan. 8, 19524: Sheets-Sheet 5 ll 26 llii llll JNVENTOR.

FLLEMON T. LEE.

A'T-roFeNEvs MW. 13, F. T. LEE MACHINE FOR SHREDDING PAPER OR THE LIKEINT O STRIPS Filed Jan. 8, 1952 4 Sheets-Sheet 4 IN V EN T 0R.

FILEMQN T. LEE

mmv ATTOFQN VE- United States Patent MACHINE FUR SHREDDING PAPER OR THELIKE INTO STRIPS Filemon T. Lee, San Francisco, Calif.

Application January 8, 1952, Serial No. 265,375

2 Claims. (Cl. 164-60) The present invention relates to improvements ina machine for shredding paper or the like into strips. It embodiesimprovements over the paper shredding machine disclosed in my copendingapplication, Serial No. 94,851, filed in the United States Patent Officeon May 23, 1949, now Patent No. 2,621,567.

In designing paper shredding machines employing rotary disc cutters,experience has shown that a surface speed of approximately three hundred(300) feet per minute should be imparted to the cutters. At the sametime, it is highly desirable to employ a standard eighteen hundred(1800) revolutions per minute (R. P. M.) motor. In order to meet theserequirements, the cutter-supporting shafts are relatively small indiameter. Of course, the employment of the standard 1800 R. P. M. motorand the small diameter shafts both contribute to the reduction in thecost of manufacture.

However, these small diameter shafts, and especially when they haveconsiderable lengths, have a tendency to bow between their ends, thusreducing the efficiency of the cutters. Any attempt to insertconventional bearings of regular width along the length of the shaftwould space the cutters too far apart where the bearings are located.Moreover, combs must be positioned adjacent to the cutters to remove cutstrips of material therefrom, which would interfere with the positioningof a number of ordinary bearings along the shafts.

With these general structural requirements in mind, I have provided amachine of the character described, in which bearing-spacer rings arecarried by the combs. These rings embrace the shafts on which thecutters are mounted, and give ample support to the shafts at a pluralityof points along the lengths of the shafts. This will permit the smallerdiameters of shafts to be employed without any bowing thereof.Furthermore, these bearing rings are arranged to abut the cutter discsto space the latter from opposing faces of the combs. The bearing ringsmay be made as large in diameter as neces sary, without interfering withthe spacings between adjacent cutters.

Other objects and advantages will appear as the specification continues.The novel features will be set forth in the claims hereunto appended.

Drawings For a better understanding of my invention, reference should behad to the accompanying drawings, forming part of this application, inwhich:

Figure l is a fragmentary front elevation view of a machine forshredding paper or the like into strips, and constructed in accordancewith the present invention;

Figures 2, 3 and 4 are oblique views of the spacerbearing ring, disccutter, and comb, respectively, which form a unit in my machine.

Figure 5 is an enlarged view of the left-hand portion of Figure 1,illustrating the assembly sequence of the cutters, combs and bearingrings for one-eighth inch /s") shreds;

2,770,302 Patented Nov. 13, 1956 'icei Q annexed claims withoutdeparting from the spirit thereof.v

Detailed description Referring now to Figures 1, 5 and 6, I show upperand. lower shafts A and B, respectively, which are mounted in paralleland spaced-apart relation with one another.. These shafts are rotatablyjournalled in bearings 10 carried by a supporting frame designatedgenerally at C. (See Figure 5.) Intermeshing gears 11 are fixed to theseshafts (see Figure l) for rotating the latter in opposite directionswith respect to each other, as suggested by the arrows 12 (see Figure6), when rotary motion is imparted to a driven pulley 14 secured to theshaft B (see Figure 1). Belts 15 are provided for driving this pulleyfrom a motor (not shown), which preferably has a speed of 1800 R. P. M.

It will be noted from Figure 6 that shreds or strips 16 may be cut fromstock material D, such as paper, which is arranged on an in-feed table17. This material is advanced along the table in the direction of thearrow 18 so as to pass between the shafts A and B. A lateral guide 19may be provided in the table to assist in directing the stock materialtoward the shaft.

In Figures 1 to 6, inclusive, the machine has been assembled for cuttingone-eighth inch /s") shreds or strips from the material D, However, I donot wish to be limited in this regard. As the specification proceeds, Ishall point out the manner in which the machine may be converted forproducing one-quarter inch (MU) strips in connection with Figure 7,while conversion to cutting one-half inch (*/2) strips will be set forthwhen describing Figure 8. Of course, other widths of strips may beproduced.

Regardless of the width of strips desired, a plurality of disc cuttersE, combs F, and spacer-hearing rings G are provided for each of theshafts A and B. The disc cutters on one shaft are interjacent thecutters on the other shaft. As the specification continues, it willappear that the width of the strips 16 cut from the material D dependsupon the predetermined manner in which the disc cutters and the combsare arranged upon the rotatable shafts.

Each disc cutter E has a peripheral groove 20 extendingcircumferentially therearound, and is fashioned with an axial opening 21adapted to telescopically receive one of the rotatable shafts. Thelatter are formed with keyways 22 extending lengthwise thereof toreceive keys 23, which project inwardly from each disc cutter into itsopening 21 (see Figure 3). The grooves 20 in the cutters are for thepurpose of aiding in traction for feeding the material between thecutters. Moreover, these grooves guide the material in a straight line,preventing it from moving into the cutters at an angle.

By way of example, the cutters E may have a thickness of one-eighth ofan inch 0A3) between its opposing side faces 24 (see Figure 3). However,no dimensional limitation is intended in this connection. Quiteobviously, the disc cutters may have greater or less thickness.

All of the combs F are identical with each other. As illustrated inFigures 4 and 6, each is provided with a ring-receiving opening 25extending therethrough so that the combs may be telescoped over theshafts A and B. Each comb is made in the nature of a plate having a 3semi-cylindrical crown 26, diverging sides 27 and a base 28. Curvednotches 7.9 'are provided in each comb at the junction of the crown26and the sides 27, which register with the peripheries of the disccutters (see Figure 6). he combs on each shaft are interjacent thecutters on the shaft,

As the strips 16 emerge from the cutters E at the front end of themachine, there is, a tendency for them to follow the revolving cutters.strips are projected into the notches 29 disposed on the left-hand. sideof Figure 6, which results in forming kinks 30 that glide out of thenotches. After short relatively straight sections 31 of the strips havecleared these notches, the strips are pulled again into the notches, due

to the revolving cutters tending to carry the strips therewith,producing other kinks 32 in the strips. These its are fashioned in thestrips at intervals throughout the lengths thereof to produce zigzagstrips having a certain amount of rigidity, and at the same timerequiring less material for packaging merchandise or the like. When thewalls of the comb defining the notches 2? at one side of the comb Weardown, the combs may be reversed to present the other notches 29 at thedischarge side of the cutters.

It will be seen that a spacer-bearing ring G is provided for each of thecombs. The bore 33 of each ring is dimensioned for sliding over theshafts A or B, while the outer periphery 34 has a running fit with thewall defining the ring-receiving opening 25 of each comb. The rings.turn with the shafts around which they are applied.

In actual practice, the width of each ring G between its opposing faces35 (see Figure 2) is slightly greater than the thickness of each comb.This will allow the bearing ring to project beyond the opposing sides 36of the combs F (see Figure Thus, the rings G serve to space the oppositefaces 24 of the cutters E from the comb sides 36 when the cutters,spacers and combs are assembled on their respective rotating shafts.Also, the bearing rings are slightly wider than the cutters so that thecutters on one shaft will not bind against those on the other shaft.

For the purpose of precluding the shafts A and B from flexing away fromone another, rigid upper and lower plates 37 and 33 are mounted on thesupporting frame C in parallel and spaced-apart relation with eachother. These plates define confronting parallel flat surfaces 370: and38a, respectively (see Figures 5 and 6). The bases 28 of the combsassociated with the shaft A abut. the upper plate 37 along the said flatsurface ofthe latter, while the bases of the combs surrounding the shaftB rest against the lower plate 38 along the said flat surface of thelatter. These plates may be reinforced by ribs 39 (see Figure 6); and,if desired, a cover plate 40 may be arranged over the ribs of the upperplate.

In order to add further support to the combs F and thereby retain theshafts A and B from flexing away from one another when the material D isbeing cut, I have provided pairs of retaining rods 41 above and belowthe shafts A and B, respectively. These rods telescope through openings42 formed in the plate-like combs, and have their ends anchored insockets 43, which are secured to the supporting frame. The combs areslidable longitudinally along these rods, and thus permit the combs Fand their hearing rings G to float therealong totake care of expansiondue to heat. Moreover, the plates 37 and 3t and rods 1 prevent the combsfrom turning about their respective shafts.

Reference to Figures 4 and 6 discloses radial grooves 44 as being madein the combs to allow oil to be introduced to the bearing rings forlubricating the latter.

In Figure 1, I show collars 45 as being anchored to the shafts A and Btoward the right-hand ends thereof, while split lock nuts 46 areadjustably fastened near the left-hand ends of these shafts. The purposeof these collars and lock nuts is to retain the cutters E, combs F Theleading ends of the and bearing rings G in assembled relation withrespect to the shafts A and B.

The sequence of assembling the various parts for obtaining one-eightinch shreds or strips 16 of cut material will be understood by referringto Figure 5. It will be noted therein that the first item to be placedon the lower shaft B next to the split lock nut 46 thereof is a disccutter E. This is followed by a comb F and its bearing ring G. However,on the upperjshaft A, a comb and its bearing ring are appliednext to thelock nut 46 on this shaft, followed by a cutter E. In assembling, careshould be taken to assure the fact that the combs and bearingrings ontheshaft A are disposed ;in alignment opposite the cutters on the shaft B,and vice versa.

The mechanic continues placing the cutters, combs and bearing rings onthe two rotating shafts until the required number of each have beentelescoped thereonto. When all are assembled, the lock nuts 46 aretightened in place, leaving the proper clearance between the cutters.

When assembling the machine for producing onequarter inch 0A1) shreds 0rstrips, as shown in Figure 7,- the same general procedure is followed,excepting for the fact that two of the cutters E are grouped together,and a pair of combs F and their bearing rings G are interposed betweenadjacent groups of cutters on each of the shafts A and B. As clearlyillustrated in this arrangement (Figure 7), the pairs of cutters ontheshaft B are mounted in alignment opposite the pairs of combs on theshaft A, and vice versa. The combined widths of each pair of cutterswill provide strips of the desired size. For the sake of simplicity, theremaining parts of the machine have been omitted from Figure 7. Also,toward the right side in this view cutters E and combs F are shown inseparated relation and being moved into place along the shafts.

In Figure 8, I show the assembly of the parts for cutting one-half inch/2") shreds or strips. The same procedure is followed, as previouslyexplained, except in this case four cutters E are grouped together,followed by four. combs F and their spacer-bearing rings G. Again, thecutters on one shaft are arranged opposite combs on the other shaft, andinterjacent the cutters on the other shaft. The right side of Figure 8illustrates cutters E and combs F being advanced into place along thelower shaft. The

assembled combs on each shaft are interjacent the cutters on the shaft.

Quite obviously, other widths of strips may be cut Summary of operationAssuming that the machine has beenset up as shown in Figures 1, 5 and 6,for cutting one-eighth inch shreds or strips 16 from the material D,power is applied to the driven pulley 14 so as to rotatethe shafts A andB in opposite directions relative to one another, as suggested I by thearrows 12 in Figure 6.

Initially, a small stack of the vmaterial D, for instance paper, 18placed on the iii-feed table 17.. Thenthe operator starts shredding witha fewthicknesses of paper,

by advancing the latter between the rotating disccutters E. The amountof paper may be gradually increasedto determine how many thicknesses ofpaperthe machine will cut beforestalling. By experimenting, the operatorwill soon get the feel of they right amount to feed, the cutters orshredder, at one time. i

The changeover of the machine to produce different The, shredder .willde-. hver a greater output when not fed too heavily; the,

shredder will take normal feedings more rapidly than the operator canfeed it.

As the paper is advanced along the infeed table, as suggested by thearrow 18 in Figure 6, it will be severed into a plaurality of strips 16by the rotating cutters E. These strips will tend to follow the cutters,but will be removed therefrom by the interposed combs F. The cut stripswill be projected into the notches 29 arranged at the out-feed side ofthe cutters (left side of Figure 6), kinking the strips at intervals,such as 30 and 32. These strips will fall into an inclined dischargechute 47 (see Figure 6).

In converting the machine to cut strips of one-quarter inch 4") widths,the cutters E and combs F are mounted on the shafts A and B in themanner shown in Figure 7. Likewise, the machine may be set up to deliverstrips of one-half inch /2) widths by rearranging the cutters and combson the shafts A and B in the way illustrated in Figure 8.

As previously pointed out, other combinations of the cutters and combsmay be resorted to for cutting strips of other widths. Also, thinner orthicker cutters and combs may be provided within the spirit of theinvention.

It is of particular importance that the combs F, their bearing-spacerrings G and the rigid plates 37-38 are arranged to prevent the shafts Aand B from flexing or bowing away from one another. This maintains thecutters in proper relation for effecting shredding the paper, or othermaterial.

I claim:

1. In a machine for shredding paper or the like into strips, 21 frame, apair of parallel shafts journaled at spaced complementary points in saidframe, a plurality of spaced disc cutters mounted on each shaftintermediate said journals with the cutters on one shaft beinginterjacent the cutters on the other shaft, means for rigidly supportingsaid shafts intermediate the journal points and for maintaining thecutters in fixed relationship on said shafts comprising a plurality ofcombs mounted on each shaft, the combs on each shaft being interjacentthe cutters on the same shaft and being opposite the cutters on theother shaft, the combs each having fiat bases extended transversely ofthe shafts with the fiat bases of the combs on one shaft extendingparallel to the flat bases of the combs on the other shaft, said framehaving an upper plate and a lower plate defining flat facing parallelsurfaces, the flat bases of the combs on one shaft being seated on oneof said surfaces, and the fiat bases of the combs of the other shaftbeing seated on the other of said surfaces, means for connecting saidcombs to the respective shafts comprising a ring associated with eachcomb, each ring having a sliding fit with its associated shaft and arunning fit with its associated comb and projecting outwardly of thecomb on each side thereof to space each comb from the elements adjacenteach comb on the associated shaft, said surfaces and bases beingperpendicular to a line extending diametrically through both shafts andparallel to the normal line of feed of material to said cutters.

2. In a machine for shredding paper or the like into strips, a frame, apair of parallel shafts journaled at spaced complementary points in saidframe, a plurality of spaced disc cutters mounted on each shaftintermediate said journals with the cutters on one shaft beinginterjacent the cutters on the other shaft, means for rigidly supportingsaid shafts intermediate the journal points and for maintaining thecutters in fixed relationship on said shafts comprising a plurality ofcombs mounted on each shaft, the combs on each shaft being interjacentthe out ters on the same shaft and being opposite the cutters on theother shaft, the combs each having fiat bases extended transversely ofthe shafts with the flat bases of the combs on one shaft extendingparallel to the fiat bases of the combs on the other shaft, said framehaving an upper plate and a lower plate defining flat facing parallelsurfaces, the flat bases of the combs of one shaft being seated on oneof said surfaces, and the flat bases of the combs of the other shaftbeing seated on the other of said sur faces, means for connecting saidcombs to the respective shafts comprising a ring associated with eachcomb, each ring having a sliding fit with its associated shaft and arunning fit with its associated comb and projecting outwardly of thecomb on each side thereof to space each comb from the elements adjacenteach comb on the associated shaft, said surfaces and bases beingperpendicular to a line extending diametrically through both shafts andparallel to the normal line of feed of material to said cutters, a pairof retaining rods extending parallel to said shafts and through each ofthe combs associated with one shaft and having a sliding fit with thecombs, said rods being spaced from said surfaces and from said shafts,said rods being secured to said frame, and a pair of retaining rodsextending parallel to said shafts and through each of the combsassociated with the other shaft and having a sliding fit with the lattercombs, the last named rods being spaced from said surfaces and from saidshafts, and being secured to said frame.

References Cited in the file of this patent UNITED STATES PATENTS1,178,386 Edwards Apr. 4, 1916 1,319,496 Stachowski Oct. 21, 19192,106,896 McCullough et al. Feb. 1, 1938 2,202,843 Edwards June 4, 19402,554,114 Menkin May 22, 1951 2,621,567 Lee Dec. 16, 1952 2,679,900Bottenhorn June 1, 1954 FOREIGN PATENTS 65,852 Norway Mar. 1, 1943

